Many transfusion-transmitted viruses have envelopes. These include human immunodeficiency virus (HIV), human lymphotropic virus, type I (HTLV-1), cytomegalovirus (CMV) and Epstein-Barr virus (EBV). Monoglycerides and free fatty acids have been shown to have antiviral activity when incubated with enveloped viruses; all enveloped viruses tested were equally susceptible to lipid inactivation. The overall aim of this proposal is to develop antiviral mixtures of monoglycerides which will inactivate blood- borne enveloped viruses withour destroying the biological activity of blood and blood products. The concentrations of antiviral monoglycerides, either individually or in mixtures, required to inactivate HIV, CMV, herpes simplex virus-1 and other enveloped viruses in packed red cells, plasma, plasma products and whole blood will be determined. Blood and blood products will be examined following treatment with antiviral monoglycerides to determine if their biological activity is affected by lipid treatment. Monoglyceride mixtures which are antiviral but not hemolytic will be developed for use with packed red blood cells and whole blood. Also, monoglyceride mixtures which are antiviral and lyse red blood cells and leukocytes will be developed for use with plasma and plasma products. Finally, monoglyceride mixtures will be developed which will inactivate any leukocytes found with packed red blood cells without producing hemolysis because lymphocytes and other leukocytes are carriers of HIV, CMV and other enveloped viruses and can survive for an extended period of time in stored blood and blood products